OBJECTIVE: To optimize the preparation technology of phloroglucinol phospholipids complex and study its physicochemical properties.METHODS: The preparation technology for phloroglucinol phospholipids complex was optimized taking the molar ratio of phloroglucinol to phospholipids(A),reaction temperature(B) and reaction time(C) as factors and complex ratio of phloroglucinol and phospholipid as index.The dissolubility and oil/water partition coefficient of the complex in different solvents were determined and compared with crude drug,and the new complex's physicochemical properties were validated by UV and IR(infrared spectra).RESULTS: The optimized preparation conditions for phloroglucinol phospholipids complex were obtained as follows: A was 1∶2;B was 60 ℃ and C was 2 h.The complex ratio remained at above 98%.Compared with phloroglucinol crude drug,the phloroglucinol phospholipids complex in water or chloroform showed increase in both dissolubility and oil/water partition coefficient.UV and IR confirmed that no new complex had been formed from phloroglucinol and phospholipids.CONCLUSION: The optimized technology greatly enhanced the dissolubility and lipotropy of the phloroglucinol phospholipids complex.

Objective To detect Porphyromonas gingivalis and clinical index in subgingival specimens after removal of orthodontic appliances and to evaluate clinical index and P.gingivalis factors associated with orthodontic appliances during an episode of gingival inflammation and the impact of appliance removal on periodontal health.Methods Choose 20 patients prepare to removal of orthodontic appliances.Plaque index(PLI),sulcus bleeding index(SBI) and probing depth(PD) of observed teeth were examined and subgingival plaques were collected at prior to appliance removal(baseline) and 1,3 and 6 months after appliance removal.The numbers of P.gingivalis,total bacteria,the proportion of P.gingivalis and the prevalence of P.gingivalis in the samples were detected with the TaqMan real-time PCR.Results The prevalence of P.gingivalis decreased from baseline to the 6th month after fixed appliance removal in two groups,and significant change was found in 6th month(P ＜ 0.05); The numbers of P.gingivalis significantly reduced from baseline to the 6th month(P ＜ 0.05); The proportion of P.gingivalis in subgingival plaque decreased from baseline to the 6th month(P ＜0.05).PLI,SBI and PD significantly decreased from baseline to the 6th month after fixed appliance removal.Conclusion After fixed appliance removal,most of patients can recover periodontal tissue health in good oral hygiene.The percentage of P.gingivalis are closely associated with periodontal status.TaqMan real-time polymerase chain reaction has a high sensitivity and specificity.It was demonstrated the broad potential of application on detection of oral microbes.

OBJECTIVE： To prepare Melatonin solid lipid nanoparticles （MT-SLNs）， and to investigate in vitro transcutaneous absorption characteristics of them in isolated skin of mice. METHODS： Using melatonin （MT） as model drug， glycerin sorbate as oil phase， poloxamer 188 （F188） as emulsifier， MT-SLNs was prepared by melt-emulsion method. The morphology of MT-SLNs was observed by TEM； the particle size distribution of MT-SLNs was measured by laser particle size analyzer， and the infrared spectrum characteristics were measured by infrared spectroscopy. The entrapped efficiency and drug loading amount were determined by HPLC and ultrafiltration centrifugation method. The transcutaneous absorption characteristics in vitro of MT-SLNs and MT raw material were compared using Franz diffusion cells method. RESULTS： The formulation of MT-SLNs included 2.5 mg/mL MT raw material， 25 mg/mL glycerin sorbate and 1％F188. The obtained MT-SLNs were spherical， and no aggregation was observed. Average particle size was （67.88±0.17）nm， and polydispersity index was 0.188±0.001. The characteristic absorption peaks of N—H stretching and bending vibration were not found in infrared spectra， and the characteristic absorption peaks of C—H stretching vibration of benzene ring shifted red to 1 750 cm－1. The entrapped efficiency and drug loading amount of MT-SLNs were （87.54±5.31）％ and （8.42±0.78）％. The transcutaneous absorption behavior of MT-SLNs and MT raw material conformed to zero-order kinetics release rule. The steady-state transmission rate of MT-SLNs [（31.71+2.78） μg/（h·cm2）] was significantly higher than that of its raw material [（10.32±3.24） μg/（h·cm2）]， and its lag time [（0.17±0.01） h] was significantly shorter than that of its raw material [（1.57±0.37） h] （P＜0.01）. CONCLUSIONS： Prepared MT-SLNs have small particle size and distributed evenly， and can promote in vitro transcutaneous absorption.